1. Field of the Invention
The present invention relates to an optical signal transmission device, and more particularly to a device for suppressing stimulated Brillouin scattering to enable transmitting a higher than ever energy optical signal via an optical fiber device.
2. Description of The Related Art
In general, unification of spectra and enhancement of low loss performance of optical fibers have been advanced with the view of speeding up signal transmission and lengthening the distance between transit trunks. At present, high power transmission output by means of an optical fiber amplifier is desired in order to realize even greater distances.
In the prior art, in order to reduce influence on the transmission quality based on the dispersion of light in optical fiber, longer distances have been attempted by means of a unified mode of a laser diode as a light source, an increase in modulation rate based on the external modulation mode, increased power output of an optical transmitting output or the like. Nevertheless, based on the effect of stimulated Brillouin scattering generated by the optical fiber in a transmission line, a phenomenon that an error rate is increased, has occurred frequently.
Accordingly, even if the gain of an optical amplifier is increased, an optical transmission output cannot surpass a threshold value (for example, +9 dBm) in which the stimulated Brillouin scattering could occur, and a problem occurs which makes it impractical to utilize a high output provided by the optical amplifier.